In-situ tear sample collection and testing using a contact lens

ABSTRACT

Apparatus, systems and methods employing contact lenses having one or more sensor that sense an analyte in tear fluid and one or more recesses that collect the tear fluid. In some aspects, a contact lens includes a substrate that forms at least part of a body of the contact lens and a recess formed within the substrate configured to collect tear fluid when the contact lens is worn. The contact lens further includes at least one sensor disposed within the substrate configured to sense presence of an analyte in the collected tear fluid.

TECHNICAL FIELD

This disclosure generally relates to a contact lens employing one ormore recesses integrated within a substrate that collect tear fluid andsupply collected tear fluid to a sensor for sensing of an analytetherein.

BACKGROUND

Tear fluid provides a viable source of biological analytes that canindicate various health states of an individual from which tear fluid isgenerated. However, collection of tear samples for testing is difficult.Many processes for collecting tear samples usually irritate the eye andproduce tear fluid having constituents which can lead to erroneous testresults. For example, tear fluid generated from irritation of an eye,such as touching of the eye and tear fluid generated from an emotionalreaction comprise different constituents than basal tears and aregenerally produced in greater quantity than basal tears. Such reflex andemotional tears interfere with composition of tear samples of interest.

In order to avoid some of the aforementioned drawbacks associated withcollection of tear fluid, contact lenses have been established thatemploy internal sensing platforms for in-situ testing of tear fluid foranalytes. These contact lenses generally test tear fluid that forms atear film over the contact lens. However, the total volume of tear fluidestablishing the tear film is often insufficient for in-situ testing ofvarious analytes.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A illustrates an example contact lens having a recess forcollecting tear fluid and having a sensor for sensing an analyte in thecollected tear fluid in accordance with aspects described herein.

FIGS. 2A and 2B illustrate additional examples of contact lenses havingone or more recesses for collecting tear fluid and having a sensor forsensing an analyte in the collected tear fluid in accordance withaspects described herein.

FIG. 3A-3C illustrate examples contact lens having a plurality ofrecesses for collecting tear fluid and/or having a plurality of sensorsfor sensing one or more analytes in the collected tear fluid inaccordance with aspects described herein.

FIG. 4A-4B illustrate top planar views of examples of contact lenseshaving a plurality of recesses for collecting tear fluid and having asensor for sensing an analyte in the collected tear fluid in accordancewith aspects described herein.

FIG. 5 presents an illustration of an exemplary non-limiting system thatincludes a contact lens that facilitates sensing and determininginformation associated with an analyte present within tear fluidgenerated by a wearer of the contact lens in accordance with aspectsdescribed herein.

FIG. 6 is a high level illustration of an example contact lens circuitfor employment in a contact lens to facilitate gathering, processing andwirelessly communicating, sensed information related to an analytepresent in tear fluid collected in a cavity disposed within the contactlens, accordance with aspects described herein

FIG. 7 presents an exemplary reader device for receiving, from a contactlens, information related to an analyte sensed in tear fluid collectedby the contact lens in accordance with aspects described herein.

FIG. 8 is an exemplary flow diagram of a method that facilitatescollecting tear fluid with a contact lens, and sensing an analyte in thecollected tear fluid in accordance with aspects described herein.

FIG. 9 is an exemplary flow diagram of a method that facilitatescollecting tear fluid with a contact lens, sensing an analyte in thecollected tear fluid, and transmitting information associated with thesensed analyte in accordance with aspects described herein.

FIG. 10 is an illustration of a schematic diagram of an exemplarynetworked or distributed computing environment with which one or moreaspects described herein can be associated.

FIG. 11 is an illustration of a schematic diagram of an exemplarycomputing environment with which one or more aspects described hereincan be associated.

DETAILED DESCRIPTION

In one or more aspects, the disclosed subject matter relates to acontact lens that facilitates in-situ tear fluid testing. In someaspects, the contact lens includes a substrate that forms at least partof a body of the contact lens and a recess formed within the substrateconfigured to collect tear fluid when the contact lens is worn. Thecontact lens further includes at least one sensor disposed within thesubstrate configured to sense presence of an analyte in the collectedtear fluid.

In another aspect, a method is disclosed that includes collecting tearfluid in a cavity disposed within a body of a contact lens and detectingpresence of at least one analyte in the collected tear fluid via atleast one sensor located within the body of the contact lens. In oneaspect, the at least one sensor is located within the cavity. In anotheraspect, the at least one sensor is located adjacent to the cavity andthe cavity includes an opening through which the tear fluid contacts theat least one sensor. According to this aspect, the method can includedispensing a portion of the tear fluid from the cavity via the openingso that the portion of the tear fluid contacts the at least one sensor.

In another embodiment, a contact lens is provided having a tear fluidcollection recess formed in a substrate that forms at least part of abody of the contact lens and configured to collect tear fluid when thecontact lens is worn. The contact lens further includes at least onesensor configured to sense presence of one or more analytes the tearfluid and a processor configured to determines or infer type orconcentration of the one or more analytes. A transmitter is alsoincluded on or within the contact lens configured to transmitinformation relating to type or concentration of the one or moreanalytes to an external device.

Various aspects are now described with reference to the drawings,wherein like reference numerals are used to refer to like elementsthroughout. It should be appreciated that one or more aspects of thedrawings from are not drawn to scale. In the following description, forpurposes of explanation, numerous specific details are set forth inorder to provide a more thorough understanding of one or more aspects.It is be evident, however, that such aspects can be practiced withoutthese specific details. In other instances, structures and devices areshown in block diagram form in order to facilitate describing one ormore aspects.

With reference now to the drawings, FIG. 1 illustrates a cross-sectionalview of an example tear fluid collecting contact lens 100 in accordancewith aspects described herein. Contact lens 100 includes a recess orcavity 106 for collecting tear fluid and having a sensor 108 for sensingan analyte in the collected tear fluid when the contact lens 100 is wornover an eye 104. As used herein the terms recess and cavity are usedinterchangeably. The recess 106 is configured to collect tear fluid overtime as the contact lens 104 is worn over an eye. In an aspect, therecess 106 collects tear fluid via capillary action and/or osmosis. Thecollected tear fluid serves as a reservoir of tear fluid for analytesensing processes of sensor 108.

In particular, tear fluid provides a viable source of biologicalanalytes that can indicate various health states of the individual fromwhich the tear fluid is generated. Contact lenses having integratedsensors for sensing various analytes generally test analytes present intear fluid that forms a tear film over the contact lens. However, thetotal volume of tear fluid establishing the tear film is ofteninsufficient for in-situ testing of various analytes. For example,electrochemical sensors can be employed within a contact lens thatperform oxidation or reduction of an analyte of interest and measurecurrent generated in association with oxidation or reduction. However,when to ear film serves as a sole source of analyte, continuous sensingby an electrochemical sensor is often compromised because the limitedamount of analyte in the tear film can be quickly consumed by thesensor.

Contact lens 100 is depicted having a single cavity 106. However invarious aspects, contact lenses disclosed herein can include anysuitable number N of cavities, N is an integer. Cavities, such as cavity106 provided within the disclosed tear fluid collecting contact lenses,such as contact lens 100, can fill with tear fluid over a period of timedependant on size and shape of cavities. Further, tear collectingcavities provided within contact lenses disclosed herein can slowly fillwith tear fluid over time so as not to dry out an eye. It is to beappreciated that the contact lens can be designed and configured tocollect tear fluid over any suitable range of time (e.g., seconds,minutes, hours, days, weeks, or months). In an aspect, the cavities areconfigured to store collected tear fluid while the contact lens is wornin the eye, and when the contact lens is removed from the eye.

As illustrated in FIG. 1, cavity 106 and sensor 108 are located within abody or substrate 102 of the contact lens 100. In an aspect, thesubstrate 102 is a hydrogel—the contact lenses disclosed herein cancomprise any suitable material that can be employed to create one ormore tear colleting cavities within the substrate 102. In an aspect, thecontact lenses disclosed herein can include soft lenses made from one ormore soft polymer materials including but not limited to, a hydrogel, asilicone based hydrogel, a polyacrlyamide, or a hydrophilic polymer. Forexample, in an aspect, contact lenses disclosed herein can includecrosslinked hydrogels including hydrophilic monomers (e.g.N-Vinylpyrrolidone, N,N-dimethylacrylamide, 2-hydroxyethyl methacrylate,hydroxyethyl acrylate, methacrylic acid and acrylic acid), strengtheningagents, ultraviolent light (UV) blockers, or tints. In another aspect,contact lenses disclosed herein can include silicone hydrogels (e.g.crosslinked hydrogels containing silicone macromers and monomers, aswell as hydrophilic monomers that absorb water). In yet another aspect,contact lenses disclosed herein can include hard lenses made from one ormore rigid materials including but not limited to, a silicone polymer,polymethyl methacrylate, or rigid gas permeable materials.

Although not to be limited to such shape, the contact lenses disclosedherein, such as contact lens 100, are generally provided in a sphericalshape that conforms to shape of an eye. With reference to FIG. 1,contact lens 100 include two primary surfaces, an inner surface 112 andan outer surface 110, both of which are spherical. The inner surface 112is concave and is shown facing and resting on a surface of the eye 104,and conforming to shape of cornea 114—the outer surface 110 is convex.

In an aspect, as depicted in FIG. 1, a cavity 106 is located within thesubstrate 102 and adjacent outer wall 112. According to this aspect,cavity 106 is designed to collect tear fluid disposed on the outersurface of the contact lens 102. It is to be appreciated that cavity 106includes an opening or diffusion layer adjacent the outer surface 110 ofthe contact lens at which tear fluid enters via capillary action and/orosmosis respectively. In other aspects, tear collecting cavities aredisposed within the substrate 102 and adjacent to the inner surface 112or a perimeter edge of the contact lens 100. Regardless of location of acavity within the substrate, the respective cavity includes an openingand/or diffusion layer adjacent to a surface of the contact lens thatfacilitates influx of tear fluid.

In an aspect, a cavity 106 can be located within the substrate at ornear a perimeter of the substrate so that the cavity is not located infront of the cornea 114 of the eye when the contact lens in worn in theeye. According to this aspect, a cavity provided within the substrate ofa contact lens can have a length slightly less than a radius (midwaypoint R of FIG. 1) of the contact lens. However a cavity may be providedwithin a contact lens having a length that ranges substantially thelength or diameter (dashed line D) of the substrate.

Cavities disposed within the disclosed contact lenses, such as cavity106 of contact lens 100, can have any suitable size and shape thatfacilitate collection of tear fluid without irritating the eye, withoutdisrupting the functions of the eye, without disrupting function of thecontact lens, and without causing discomfort to the wearer. For example,cavity 106 can have a rectangular shape (as depicted in FIG. 1), acylindrical shape, or a semi-ellipsoid shape. In various aspects, cavity106 has an optimal size that facilitates collecting an amount of tearfluid for performing continuous sensing by a sensor 108 when the tearfluid is provided to the sensor 108. Accordingly, the size and shape ofa cavity can vary depending on functions of sensor 108 that will besensing the tear fluid collected within the cavity.

Contact lens 100 (and additional contact lenses described herein) has athickness or width that spans in a horizontal direction between innersurface 112 and outer surface 110. In general aspects, the width of thelens is thickest (relative to the width of the lens at other areas ofthe lens) at the center point of the lens, tapering outwardly to aknifelike edge at the perimeter of the lens. Dashed line W indicatesdirection of the width or depth of the contact lens 100. The diameter ofthe contact lens 100 is indicated by dashed line D. The particulardimensions (including dimensions attributable to thickness, diameter,curvature, and etc.) of the subject contact lenses are not critical andmay vary.

In an aspect, a cavity, such as cavity 106 provided within the substrateof a contact lens, such as contact lens 100, can have a depth that spanswithin the thickness or width W of the substrate, including the entirethickness. For example, the thickness or width of the substrate of acontact lens can range about 1.0 μm to about 400 μm depending on type oflens and distance from center point. Generally, contact lenses have athickness of about 50 μm to about 150 μm. In typical human eyes, thetear film has a general thickness of about 7-8 μm while the total volumeof tears in an eye is about 6-8 μL. With this in mind, for every 10 μmof depth of a tear collecting cavity (e.g. cavity 106), available volumeof tears for consumption by a sensor within the contact lens (e.g.sensor 108) can be doubled as compared to available tears in regulartear film.

In an aspect, where the substrate has a thickness of about 400 μm, acavity can have a width or depth of about 400 μm or less and about 10μm, more particularly, a depth of about 150 μm or less and about 25 μm,and even more particularly, a depth of about 100 μm or less and about 50μm. In another aspect, where the substrate has a thickness of about 150μm, a cavity can have a width or depth of about 150 μm or less and about10 μm, more particularly, a depth of about 100 μm or less and about 25μm, and even more particularly, a depth of about 75 μm or less and about50 μm.

In an embodiment, cavities provided within the subject tear collectingcontact lenses are considered microcavities. The term microcavity asused herein includes cavities, channels, cells, or other cavity capableof collecting and storing tear fluid having a volumetric size less thanthe entire volume of the substrate in which it is located. In an aspect,the total volume of the contact lens substrate is about 25 to about 50micro liters. With this in mind, in an aspect, a microcavity has avolume less than about 50% of the total volume of the substrate. Inanother aspect, a microcavity has a volume less than about 25% of thetotal volume of the substrate. In another aspect, a microcavity has avolume less than about 10% of the total volume of the substrate. In yetanother aspect, a microcavity has a volume less than about 5% of thetotal volume of the substrate. In yet another aspect, a microcavity hasa volume less than about 0.1% of the total volume of the substrate.Still in yet another aspect a microcavity has a volume less than about0.01% of the total volume of the substrate.

Referring back to FIG. 1, contact lens 100 (and additional contactlenses described herein) includes a sensor 108 configured to sense oneor more analytes within tear fluid collected in cavity 106. In anaspect, as illustrated in FIG. 1, the sensor 108 is located withincavity 106. Sensor 108 and additional sensory employed in contact lensesdisclosed herein, can include a variety of sensors configured to senseone or more analytes of interest. For example, sensors for employmentwith the disclosed contact lenses can include but are not limited to, anelectrochemical sensor, a biosensor, an amperometric sensor, or apressure sensor. Such sensors can be configured to sense informationindicative of presence and/or concentration of various analytes incollected tear fluid, including but not limited to glucose, alcohol,histamine, urea, lactate, cholesterol, or electrolyte ions such assodium, potassium, calcium and magnesium. In an aspect, sensor 108 caninclude two or more sensors configured to sense different analytes ofinterest.

Turning now to FIG. 2A presented is another cross-sectional view of anexample tear fluid collecting contact lens 200 in accordance withaspects described herein. Contact lens 200 includes a recess or cavity106 for collecting tear fluid and having a sensor 108 for sensing ananalyte in the collected tear fluid when the contact lens 200 is wornover an eye 104. Repetitive description of like elements employed inrespective embodiments of contact lenses described herein is omitted forsake of brevity.

Contact lens 200 is similar to contact lens 100 with the exception thatsensor 108 is located within the substrate 102 yet outside of cavity106. According to this embodiment, cavity 106 can include an openingand/or a diffusion layer 202 configured to release or excrete collectedtear fluid. For example, the opening 202 can include a relatively smallhole through which collected tear fluid slowly and steadily escapescavity 106 in a controlled fashion. The size and shape of the opening202 can be selected such that a predetermined amount of tear fluid isdispensed from cavity 106 at a predetermined rate. In aspect, ratherthan a hole, cavity 106 can include a diffusion layer 202 that includesa material that allows for the diffusion of tear fluid out of cavity106. The diffusion layer material can be selected such that apredetermined amount of tear fluid is dispensed from cavity 106 at apredetermined rate.

According to this embodiment, sensor 108 is provided within thesubstrate 102 outside of cavity 106 and substantially adjacent toopening 108. As tear fluid is dispensed through opening 108, it contactssensor 108. With this configuration, sensor 108 can be provided acontrolled amount of fresh tear fluid at a continuous rate. In anaspect, by separating sensor 108 from the reservoir of tear fluidcollected in cavity 106, by-products generated by the sensor 108 can beseparated from the collected tear fluid so as to not contaminate thecollected tear fluid. In addition, by providing sensor 108 with acontinuous supply of fresh tear fluid, changes in the analytecomposition of the tear fluid over time can be more accuratelydiscerned.

FIG. 2B presents another cross-sectional view of an example tear fluidcollecting contact lens 201 in accordance with aspects described herein.Contact lens 201 includes a recess or cavity 106 for collecting tearfluid and having a sensor 108 for sensing an analyte in the collectedtear fluid when the contact lens 201 is worn over an eye 104.

Contact lens 201 is similar to contact lens 100 with exception ofinclusion of two or more cavities 106 provided within the substrate anddisposition of cavities 106 and sensors 108 within the substrate 102.According to this embodiment, cavity 106 is disposed within thesubstrate 102 such that depth of the cavity spans substantially parallelwith diameter D of the substrate. Cavities 106 are adjacent to outersurfaces 110 of the substrate 102 towards an outer perimeter of thecontact lens. In particular, a cavity 106 has a width W that spanswithin the thickness of the substrate, substantially perpendicular tothe inner 112 and outer 110 surfaces of the substrate, and a depthgreater than the width that spans substantially parallel to the inner112 and outer 110 surfaces of the substrate. With this embodiment, depthof cavity 106 can be increased to a depth greater than thickness of thesubstrate. It should be appreciated that cavities 106 are depictedhaving a rectangular shape merely for illustrative purposes, and are notto be limited to such shape or configuration. For example, cavities 106can have a shape that substantially corresponds to the curvature of thecontact lens 201. Sensors 108 can be further located within cavities 106and adjacent to a side surface of the respective cavities.

FIG. 3A presents another cross-sectional view of an example tear fluidcollecting contact lens 300 in accordance with aspects described herein.Contact lens 300 includes a plurality of cavities 304 for collectingtear fluid. Respective cavities 304 are further associated withrespective sensors 108 for sensing an analyte in the collected tearfluid when the contact lens 300 is worn over an eye 104.

Contact lens 300 is depicted having eight cavities 304, however itshould be appreciated that contact lens 300 can include any number Ncavities. Respective cavities 304 are disposed within the substrateadjacent to outer surface 110 of the contact lens 300. According to thisaspect, cavities 304 can collect tear fluid disposed on the outersurface 110 of the contact lens. Sensors 108 can be located within thecavities 304 and/or outside the cavities, (as depicted in FIGS. 1 and 2Arespectively). In an aspect, respective sensors 108 associated with therespective cavities 304 are configured to sense presence and/orconcentration of different analytes. Therefore, contact lens 300 cansense information associated with a plurality of different analytes atthe same time while sensing mechanisms of the respective sensors 108 donot interfere with one another. For example, by-products of a firstreaction associated with a first sensor can be contained within a firstcavity. As a result, the by-products of the first reaction will notinterfere with sensing mechanisms of a second sensor disposed within asecond cavity and configured to perform a different reaction withrespect to a different analyte of interest.

FIG. 3B presents another cross-sectional view of an example tear fluidcollecting contact lens 301 in accordance with aspects described herein.Contact lens 301 includes a plurality of cavities 306 for collectingtear fluid. Respective cavities 306 are further associated withrespective sensors 108 for sensing an analyte in the collected tearfluid when the contact lens 301 is worn over an eye 104. Contact lens301 is similar to contact lens 300 with exception of disposition ofcavities 306 within the substrate 102. In particular, with contact lens301, the cavities 306 are located adjacent to an inner surface 112 ofthe substrate 102. According to this aspect, the cavities 306 cancollect tear fluid present on an inner surface 112 of the contact lensand/or a surface of the eye 104.

FIG. 3C presents another cross-sectional view of an example tear fluidcollecting contact lens 302 in accordance with aspects described herein.Contact lens 302 includes a plurality of cavities 308 for collectingtear fluid. In one aspect, respective cavities 308 are furtherassociated with respective sensors 108 for sensing an analyte in thecollected tear fluid when the contact lens 302 is worn over an eye 104(as depicted in the lower half of contact lens 302). In another aspect,a plurality of cavities 308 can share a single sensor 108 (as depictedin the upper half of contact lens 302).

Contact lens 302 is similar to contact lens 300 with exception ofdisposition of cavities 308 and/or one or more sensors 108 within thesubstrate 102. In particular, cavities 308 span an entire width orthickness of contact lens 302. Cavities 308 can include an openingadjacent to an inner surface 112 and/or an outer surface 110 of thesubstrate 102. In an aspect, as presented in the lower half of contactlens 302, a plurality of cavities 308 span the thickness of thesubstrate and are separated from one another by a space 310. Respectivecavities 308 in the lower half of the contact lens 302 further include asensor 108 located therein. In another aspect, as depicted in the upperhalf of contact lens 302, a plurality of cavities are provided adjacentto one another and span the thickness of the substrate. Further, theplurality of cavities 308 in the upper half of contact lens 302 canshare a single sensor 108. In an aspect, the shared sensor is locatedjust outside/external to the plurality of cavities. In another aspect,the shared sensor is located within the plurality of cavities 308.

Referring now to FIGS. 4A and 4B, depicted are top planar views ofexample contact lenses 400 and 401, respectively, worn over an eye 104in accordance with aspects described herein. In an aspect, lenses300-302 can have top planar configurations same or similar to thatdepicted of lens 400. In particular, the cross-section of lens 400 takenalong axis Y can resemble the cross-sections of lenses 300-301, wherethe cavities 106 of lens 400 and similarly lenses 300-301 are providedhaving a depth/length that spans the width of the substrate (e.g.substantially perpendicular to a surface of the lens). It should beappreciate that the number of cavities 106 depicted and proportionalsize of the cavities shown is not limiting and is merely intended forillustrative purposes. For example, lens 400 can have any number N ofcavities (where N is an integer) of varying size. The cavities 106 oflens 400 are located within the substrate 102 and are disposed a radialdistance away from the center of the lens so as not to cover the cornea114 of the eye.

With reference to FIG. 4B, presented is another top-planar view of anexample tear collecting contact lens 401 in accordance with disclosedaspects. In an aspect, lens 401 demonstrates a potential top planarconfiguration of contact lens 201. In particular, the cross-section oflens 401 taken along axis Y can resemble the cross-section of lens 202,where the cavities 106 of lens 401 and similarly lens 202, are providedhaving a depth/length that spans a length of the substrate (e.g.substantially parallel to a surface of the lens). It should beappreciated that number of cavities 106 depicted and proportional sizeof the cavities depicted (e.g. eight) is not limiting and is merelyintended for illustrative purposes. For example, lens 401 can have anynumber N of cavities (where N is an integer) of varying size. Thecavities 106 of lens 401 are located within the substrate 102 and aredisposed a radial distance away from the center of the lens so as not tocover the cornea of the eye (e.g. the pupil 112 and the iris 114). In anaspect, cavities 106 can have respective openings 402 at an outeredge/perimeter 404 of the lens 401.

With reference now FIG. 5, presented is a depiction of system 500 thatincludes a contact lens 501 that facilitates sensing and determininginformation associated with an analyte present within tear fluidgenerated by a wearer of the contact lens 501 in accordance with aspectsdescribed herein. Contact lens 501 covers at least a portion of an eye104. Contact lens 501 includes one or more recesses 502 configured tocollect tear fluid and one or more sensors 504 configured to sensepresence and/or concentration of an analyte of interest in the collectedtear fluid. Repetitive description of like elements employed inrespective embodiments of contact lenses described herein, such assensors and/or recesses is omitted for sake of brevity.

Contact lens 501 further includes a contact lens circuit 506 thatfacilitates sensing functions of the one or more sensors 504, analyzinginformation sensed by the one or more sensors 504, and wirelesslycommunicating information associated with information sensed by the oneor more sensors 504. One or more components of contact lens circuit 506can be communicatively coupled to the one more sensors 504 (e.g. usingone or more wires and/or chemically). Contact lens circuit 506 isdescribed in greater detail with reference to FIG. 6.

In an aspect, contact lens circuit 506 includes various electricaland/or machine based components that facilitate gathering informationsensed by the one or more sensors 504, analyzing the information, and/ortransmitting the information to an external reader device 510. In anaspect, the contact lens circuit 506 includes at least a communicationcomponent (not shown) configured to wirelessly transmit data associatedwith information sensed by the one or more sensors 504. For example,such information can include data indicating presence and/orconcentration of an analyte present within tear fluid generated by thewearer of lens 501 and collected in the one or more cavities 502. In anaspect, the communication component can include an antenna, such as aradio frequency (RF) antenna configured to transmit the informationusing a radio wave. In another aspect, the communication component caninclude one or more LEDs configured to transmit the information usinglight signals.

FIG. 6 is a high level illustration of example contact lens thatfacilitates gathering, processing and wirelessly communicating, sensedinformation related to an analyte present in tear fluid collected in acavity disposed within the contact lens, accordance with aspectsdescribed herein. Repetitive description of like elements employed inrespective embodiments of contact lenses and contact lens circuitsdescribed herein is omitted for sake of brevity.

As shown in FIG. 6, contact lens 501 can include one or more sensors 660and one or more tear fluid collection cavities 670. Contact lens 501further includes contact lens circuit 602. Contact lens circuit caninclude communication component 610, circuitry 620, power source 630,processor 640, and memory 650. In various embodiments, one or more ofthe sensors 660, communication component 610, circuitry 620, powersource 630, processor 640, and memory 650 can be electrically orchemically coupled to one another to perform one or more functions ofthe contact lens circuit 501. For example, one or more wires can connectthe components of contact lens circuit 602 and the one or more sensors660.

In an embodiment, aspects of contact lens circuit 602 constitutemachine-executable components embodied within machine(s), e.g., embodiedin one or more computer readable mediums (or media) associated with oneor more machines. Such components, when executed by the one or moremachines, e.g., computer(s), computing device(s), virtual machine(s),etc. can cause the machine(s) to perform the operations described.Contact lens circuit can include memory 650 for storing computerexecutable components and instructions. Processor 640 can facilitateoperation of the computer executable components and instructions bycontact lens circuit 602.

As discussed above, contact lens circuit can include a communicationcomponent 610 to facilitate sending and receiving wirelesscommunications regarding sensing of an analyte within tear fluidcollected in the one or more tear fluid collection cavities. Forexample, the communication component can include a receiver, atransmitter, a transceiver and/or a transducer. In an aspect, thecommunication component 610 includes an RF antenna that transmits andreceives data regarding sensing of an analyte within tear fluidcollected in the one or more tear fluid collection cavities.

In particular, the one or more sensors 660 are configured to senseinformation indicative of presence and/or concentration of an analyte ofinterest found within tear fluid collected in the one or more tear fluidcollection cavities. Communication component 610 can include atransducer that converts sensed information (e.g. electrical signals) atthe one or more sensors into a wireless transmittable signalrepresentative of the sensed information. For example, where a sensorincludes an electrochemical sensor, the sensed information can includean electrical signal having a voltage amplitude and/or time componentrepresentative of an amount of analyte present in tear fluid asdetermined over a period of time. The transducer and or a transmittercan further transmit the wireless signal to device external to contactlens 501 for processing thereof.

In an aspect, the communication component 610 can transmit informationrelated to a sensed analyte in response to a request. According to thisaspect, the communication component 610 can include a receiver thatwirelessly receives a request for information related to a sensedanalyte. The contact lens 501 can perform sensing of analytes incollected tear fluid and store any sensed information in memory. Inresponse to a request, the transmitter can transmit requestedinformation.

In various aspects, sensed signals captured by the one or more sensors660 are wireles sly transmitted to an external device for subsequentprocessing thereof. However, in another aspect, contact lens circuit 602performs on board processing of sensed signals. Accordingly rather thantransmitting signals representative of raw data related to a sensedanalyte (e.g. voltage amplitude signals generated by the one or moresensor where the one or more sensor are electrical sensors), processor640 can process the raw data signals. In particular, processor canprocess signals generated by the one or more sensors to make variousdeterminations and inferences based on the signals. In turn,communication component can transmit processed information relating tothe various determinations or inferences.

In an aspect, processor 640 is configured to determine presence and/orconcentration of a sensed analyte based on signals generate by the oneor more sensors. In another aspect, processor 640 can determine changesin concentration of a sensed analyte over a period of time, such asthroughout the day as the contact lens 501 is worn. Still in yet otheraspect, processor 640 can determine and/or infer various health statesof the wearer of the contact lens 501 based on a determinedconcentration of a sensed analyte.

In order to processes information generated by the one or more sensors,in an aspect, sensed signals can be stored in memory 650. Further,memory 650 can store various look-up tables and/or algorithms relatingsensed information to analyte concentration and/or health states. Forexample, the look-up tables and/or algorithms can relate voltageamplitudes and durations to an analyte concentration, such as glucose.These algorithms and/or look-up tables can further relate analyteconcentration, such as glucose concentration, to a health state, such aslow blood sugar. In some aspects, where the one or more sensors 660receive a steady flow of fresh tear fluid over the course of wear ofcontact lens 501 (e.g. as discussed with respect to FIG. 2A), memory 650can store a log of the fluctuations in a sensed analyte throughout thecourse of the wear of the contact lens. According to this aspect, forexample, memory can store a log of a wearer's glucose concentration. Inturn, processor 640 can determine information related to fluctuations ina wearer's blood sugar level throughout the day.

In an embodiment, processor 640 can employ various (explicitly orimplicitly trained) classification schemes or systems (e.g., supportvector machines, neural networks, expert systems, Bayesian beliefnetworks, fuzzy logic, data fusion engines, etc.) in connection withperforming analysis of sensed signals at the one or more sensors 660. Aclassifier can map an input attribute vector, x=(x1, x2, x3, x4 . . . ,xn), to a confidence that the input belongs to a class, such as byf(x)=confidence(class). Such classification can employ a probabilisticor statistical-based analysis (e.g., factoring into the analysisutilities and costs) to prognose or infer a state of a retina. A supportvector machine (SVM) is an example of a classifier that can be employed.The SVM operates by finding a hyper-surface in the space of possibleinputs, where the hyper-surface attempts to split the triggeringcriteria from the non-triggering events. Intuitively, this makes theclassification correct for testing data that is near, but not identicalto training data. Other directed and undirected model classificationapproaches include, e.g., naïve Bayes, Bayesian networks, decisiontrees, neural networks, fuzzy logic models, and probabilisticclassification models providing different patterns of independence canbe employed. Classification as used in this disclosure also is inclusiveof statistical regression that is utilized to develop models ofpriority.

Contact lens circuit 501 can additionally include the appropriatecircuitry 6200 to facilitate the functions of contact lens circuit. Forexample, circuitry can facilitate the transfer of electrical responsesreceived at the one or more sensor 660 to the communication component610, memory 650, and/or processor 640. Circuitry 620 can also includesignal processing hardware and software, (e.g. amplifiers, modulators,and etc.) for processing electrical signals received at the one or moresensor 660 for wireless transmission thereof.

Further, contact lens circuit 602 can include a power source 630. Powersource 630 can include any suitable power source that can providenecessary power for the operation of various components of the contactlens circuit 602. For example, the power source 630 can include but isnot limited to a battery, a capacitor, a solar power source, or amechanically derived power source (e.g., MEMs system).

In an aspect, contact lens circuit 602 does not require an onboard (e.g.on the contact lens 501) power source to operate. In one aspect, contactlens circuit 602 can receive power via wireless energy transfer (e.g.using electromagnetic inductance techniques and related components).

FIG. 7 is an illustration of an exemplary non-limiting reader device 700that interfaces with a contact lens to receive information related to asensed analyte in accordance with aspects described herein. In variousaspects, the reader device 500 can include one or more of the structureand/or functionality of reader device 510 (and vice versa).

As shown in FIG. 7, reader device 700 can include interface component710, analysis component 720, display component 730 and request component740. Aspects of device 700 constitute machine-executable componentsembodied within machine(s), e.g., embodied in one or more computerreadable mediums (or media) associated with one or more machines. Suchcomponents, when executed by the one or more machines, e.g.,computer(s), computing device(s), virtual machine(s), etc. can cause themachine(s) to perform the operations described. Device 700 can includememory 760 for storing computer executable components and instructions.A processor 750 can facilitate operation of the computer executablecomponents and instructions by device 700.

Interface component 710 interfaces with and receives from at least onecontact lens, data relating to a sensed analyte. In particular,interface component 710 can interface with contact lenses describedherein that comprise a contact lens circuit such as contact lens circuit602 and the like. In an aspect, interface component 610 employs areceiving component, such as an RF receiver, transceiver, photodetector,or IR receiver, to receive sensed and/or determined information from acontact lens comprising a contact lens circuit as described herein. Insome aspects, interfacing component 710 can receive determined orinferred information relating to concentration of a sensed analyte.According to this aspect, the contact lens can include appropriatecircuitry and components to process data sensed by one or more sensorsprovided on or within the contact lens.

In another aspect, the reader can receive raw data from a contact lensrelating to signals sensed at one or more sensor disposed within thecontact lens. For example, the interface component 610 can receivesignals indicating an amplitude and duration of an electrical signalgenerated by the one or more sensors. According to this embodiment, thereader 700 includes an analysis component 720 that can analyze receivedraw data to determine or infer information related to the sensedanalyte.

Analysis component 720 can employ same or similar functionalitydescribed with reference to processor 640. In particular, analysiscomponent 720 can determine and/or infer concentration of a sensedanalyte and/or various health states of the wearer of the contact lensfrom which raw data information was transmitted based on a determinedconcentration of the sensed analyte. In order to processes informationgenerated by the one or more sensors, in an aspect, received signals canbe stored in memory 760. Further, memory 760 can store various look-uptables and/or algorithms relating sensed information to analyteconcentration and/or health states.

Reader 700 can further include display component. In an aspect, displaycomponent generates a display corresponding to received sensor signalsand/or determined or inferred analyte concentration/health stateinformation. For example, display component 730 can include a displayscreen (e.g., a liquid crystal display screen (LCD)), that presentsinformation to a user. For example, display component 730 can present agraphical display of fluctuation in concentration of a sensed analyteover course of wear of the contact lens. Reader 700 can further includerequest component 540 configured to generate a request for sensedanalyte signals and/or determined or inferred information relating tosensed analyte signals. According to this aspect, the interfacecomponent 710 can include a transmitter that can transmit requests tothe contact lens. In an aspect, the transmitter is an RF transmitter andtransmits the instructions via a radio wave. According to this aspect,the instructions can include a data signal that can be received andinterpreted by a contact lens communication component.

FIGS. 8-9 illustrates methodologies or flow diagrams in accordance withcertain aspects of this disclosure. While, for purposes of simplicity ofexplanation, the methodologies are shown and described as a series ofacts, the disclosed subject matter is not limited by the order of acts,as some acts can occur in different orders and/or concurrently withother acts from that shown and described herein. For example, thoseskilled in the art will understand and appreciate that a methodology canalternatively be represented as a series of interrelated states orevents, such as in a state diagram. Moreover, not all illustrated actsmay be required to implement a methodology in accordance with thedisclosed subject matter. Additionally, it is to be appreciated that themethodologies disclosed in this disclosure are capable of being storedon an article of manufacture to facilitate transporting and transferringsuch methodologies to computers or other computing devices.

Referring now to FIG. 8, presented is a flow diagram of an exampleapplication of systems and apparatuses disclosed in this description inaccordance with an embodiment. In an aspect, in exemplary methodology800, a contact lens such as those described herein (e.g. 501 and thelike) is employed to sense information pertaining to an analyteconcentration provided in collected tear fluid. At 810, tear fluid iscollected in a cavity disposed within a bode of a contact lens (e.g.,using tear fluid collection cavity 670). At 820, presence of the atleast one analyte in the collected tear fluid is detected via at leastone sensor located within the body of the contact lens (e.g., usingsensor(s) 660).

Turning now to FIG. 9, presented is another flow diagram of an exampleapplication of systems and apparatuses disclosed in this description inaccordance with an embodiment. In an aspect, in exemplary methodology900, a contact lens such as those described herein (e.g., 501 and thelike) is employed to sense information pertaining to an analyteconcentration provided in collected tear fluid. At 910, tear fluid iscollected in a cavity disposed within a bode of a contact lens (e.g.,using tear fluid collection cavity 670). At 920, a portion of the tearfluid is dispensed for the cavity via an opening in the cavity. At 930,presence of the at least one analyte in the collected tear fluid isdetected via at least one sensor located within the body of the contactlens and adjacent to the opening (e.g., using sensor(s) 660). At 940,data related to the at least one analyte is transmitted to a remotedevice (e.g., using communication component 610).

Exemplary Networked and Distributed Environments

FIG. 10 provides a schematic diagram of an exemplary networked ordistributed computing environment with which one or more aspectsdescribed in this disclosure can be associated. The distributedcomputing environment includes computing objects 1010, 1012, etc. andcomputing objects or devices 1020, 1022, 1024, 1026, 1028, etc., whichcan include programs, methods, data stores, programmable logic, etc., asrepresented by applications 1030, 1032, 1034, 1036, 1038. It can beappreciated that computing objects 1010, 1012, etc. and computingobjects or devices 1020, 1022, 1024, 1026, 1028, etc. can includedifferent devices, such as active contact lenses (and componentsthereof), personal digital assistants (PDAs), audio/video devices,mobile phones, MPEG-1 Audio Layer 3 (MP3) players, personal computers,laptops, tablets, etc.

Each computing object 1010, 1012, etc. and computing objects or devices1020, 1022, 1024, 1026, 1028, etc. can communicate with one or moreother computing objects 1010, 1012, etc. and computing objects ordevices 1020, 1022, 1024, 1026, 1028, etc. by way of the communicationsnetwork 1040, either directly or indirectly. Even though illustrated asa single element in FIG. 10, network 1040 can include other computingobjects and computing devices that provide services to the system ofFIG. 10, and/or can represent multiple interconnected networks, whichare not shown.

In a network environment in which the communications network/bus 1040can be the Internet, the computing objects 1010, 1012, etc. can be Webservers, file servers, media servers, etc. with which the clientcomputing objects or devices 1020, 1022, 1024, 1026, 1028, etc.communicate via any of a number of known protocols, such as thehypertext transfer protocol (HTTP).

Exemplary Computing Device

As mentioned, advantageously, the techniques described in thisdisclosure can be associated with any suitable device. It is to beunderstood, therefore, that handheld, portable and other computingdevices (including active contact lens having circuitry or componentsthat compute and/or perform various functions). As described, in someaspects, the device can be the contact lens (or components of thecontact lens) and/or the reader described herein. In various aspects,the data store can include or be included within, any of the memorydescribed herein, any of the contact lenses described herein and/or thereader device described herein. In various aspects, the data store canbe any repository for storing information transmitted to or receivedfrom the contact lens.

FIG. 11 illustrates an example of a suitable computing systemenvironment 1100 in which one or aspects of the aspects described inthis disclosure can be implemented. Components of computer 1110 caninclude, but are not limited to, a processing unit 1120, a system memory1130, and a system bus 1122 that couples various system componentsincluding the system memory to the processing unit 1120.

Computer 1110 typically includes a variety of computer readable mediaand can be any available media that can be accessed by computer 1110.The system memory 1130 can include computer storage media in the form ofvolatile and/or nonvolatile memory such as read only memory (ROM) and/orrandom access memory (RAM). By way of example, and not limitation,memory 1130 can also include an operating system, application programs,other program components, and program data.

A user can enter commands and information into the computer 1110 throughinput devices 1140 (e.g., keyboard, keypad, a pointing device, a mouse,stylus, touchpad, touch screen, motion detector, camera, microphone orany other device that allows the user to interact with the computer1110). A monitor or other type of display device can be also connectedto the system bus 1122 via an interface, such as output interface 1150.In addition to a monitor, computers can also include other peripheraloutput devices such as speakers and a printer, which can be connectedthrough output interface 1150.

The computer 1110 can operate in a networked or distributed environmentusing logical connections to one or more other remote computers, such asremote computer 1160. The remote computer 1160 can be a personalcomputer, a server, a router, a network PC, a peer device or othercommon network node, or any other remote media consumption ortransmission device, and can include any or all of the elementsdescribed above relative to the computer 1110. The logical connectionsdepicted in FIG. 11 include a network 1170, such local area network(LAN) or a wide area network (WAN), but can also include othernetworks/buses e.g., cellular networks.

Computing devices typically include a variety of media, which caninclude computer-readable storage media and/or communications media, inwhich these two terms are used herein differently from one another asfollows. Computer-readable storage media can be any available storagemedia that can be accessed by the computer, can be typically of anon-transitory nature, and can include both volatile and nonvolatilemedia, removable and non-removable media. By way of example, and notlimitation, computer-readable storage media can be implemented inconnection with any method or technology for storage of information suchas computer-readable instructions, program components, structured data,or unstructured data. Computer-readable storage media can include, butare not limited to, RAM, ROM, electrically erasable programmable readonly memory (EEPROM), flash memory or other memory technology, or othertangible and/or non-transitory media which can be used to store desiredinformation. Computer-readable storage media can be accessed by one ormore local or remote computing devices, e.g., via access requests,queries or other data retrieval protocols, for a variety of operationswith respect to the information stored by the medium. In variousaspects, the computer-readable storage media can be, or be includedwithin, the memory, contact lens (or components thereof) or readerdescribed herein.

On the other hand, communications media typically embodycomputer-readable instructions, data structures, program components orother structured or unstructured data in a data signal such as amodulated data signal, e.g., a carrier wave or other transportmechanism, and includes any information delivery or transport media. Theterm “modulated data signal” or signals refers to a signal that has oneor more of its characteristics set or changed in such a manner as toencode information in one or more signals.

It is to be understood that the aspects described in this disclosure canbe implemented in hardware, software, firmware, middleware, microcode,or any combination thereof. For a hardware aspect, the processing unitscan be implemented within one or more application specific integratedcircuits (ASICs), digital signal processors (DSPs), digital signalprocessing devices (DSPDs), programmable logic devices (PLDs), fieldprogrammable gate arrays (FPGAs), processors, controllers,micro-controllers, microprocessors and/or other electronic unitsdesigned to perform the functions described in this disclosure, or acombination thereof.

For a software aspect, the techniques described in this disclosure canbe implemented with components or components (e.g., procedures,functions, and so on) that perform the functions described in thisdisclosure. The software codes can be stored in memory units andexecuted by processors.

What has been described above includes examples of one or more aspects.It is, of course, not possible to describe every conceivable combinationof components or methodologies for purposes of describing theaforementioned aspects, but one of ordinary skill in the art canrecognize that many further combinations and permutations of variousaspects are possible. Accordingly, the described aspects are intended toembrace all such alterations, modifications and variations that fallwithin the spirit and scope of the appended claims.

Moreover, the term “or” is intended to mean an inclusive “or” ratherthan an exclusive “or.” That is, unless specified otherwise, or clearfrom the context, the phrase “X employs A or B” is intended to mean anyof the natural inclusive permutations. That is, the phrase “X employs Aor B” is satisfied by any of the following instances: X employs A; Xemploys B; or X employs both A and B. In addition, the articles “a” and“an” as used in this application and the appended claims shouldgenerally be construed to mean “one or more” unless specified otherwiseor clear from the context to be directed to a singular form.

The aforementioned systems have been described with respect tointeraction between several components. It can be appreciated that suchsystems and components can include those components or specifiedsub-components. Sub-components can also be implemented as componentscommunicatively coupled to other components rather than included withinparent components (hierarchical). Additionally, it is to be noted thatone or more components can be combined into a single component providingaggregate functionality. Any components described in this disclosure canalso interact with one or more other components not specificallydescribed in this disclosure but generally known by those of skill inthe art.

In view of the exemplary systems described above methodologies that canbe implemented in accordance with the described subject matter will bebetter appreciated with reference to the flowcharts of the variousfigures. While for purposes of simplicity of explanation, themethodologies are shown and described as a series of blocks, it is to beunderstood and appreciated that the claimed subject matter is notlimited by the order of the blocks, as some blocks can occur indifferent orders and/or concurrently with other blocks from what isdepicted and described in this disclosure. Where non-sequential, orbranched, flow is illustrated via flowchart, it can be appreciated thatvarious other branches, flow paths, and orders of the blocks, can beimplemented which achieve the same or a similar result. Moreover, notall illustrated blocks may be required to implement the methodologiesdescribed in this disclosure after.

In addition to the various aspects described in this disclosure, it isto be understood that other similar aspects can be used or modificationsand additions can be made to the described aspect(s) for performing thesame or equivalent function of the corresponding aspect(s) withoutdeviating there from. Still further, multiple processing chips ormultiple devices can share the performance of one or more functionsdescribed in this disclosure, and similarly, storage can be providedacross a plurality of devices. The invention is not to be limited to anysingle aspect, but rather can be construed in breadth, spirit and scopein accordance with the appended claims.

1. A contact lens, comprising: a substrate that forms at least part of abody of the contact lens; a recess formed within the substrate,configured to collect and store tear fluid when the contact lens is wornon an eye and store the collected tear fluid when the contact lens isremoved from the eye, said recess having a closed end; and at least onesensor disposed within the substrate configured to sense presence of ananalyte in the collected tear fluid.
 2. The contact lens of claim 1,further comprising, a plurality of recesses formed within the substrateconfigured to collect and store tear fluid when the contact lens is wornon an eye and store the collected tear fluid when the contact lens isremoved from the eye, each of said recesses forming a closed end.
 3. Thecontact lens of claim 1, wherein the recess is formed at or about aperimeter of the contact lens.
 4. The contact lens of claim 1, whereinthe recess has a depth spanning about a thickness of a cross-sectionalarea of the substrate.
 5. The contact lens of claim 4, wherein therecess has a depth within a range of about 50 to about 400 μm.
 6. Thecontact lens of claim 1, wherein the recess has a depth within a rangeof about 10 to about 75 μm.
 7. The contact lens of claim 1, wherein theat least one sensor is located within the recess.
 8. The contact lens ofclaim 1, wherein the at least one sensor is located adjacent to therecess and wherein the recess includes an opening through which the tearfluid is dispensed and contacts the at least one sensor.
 9. The contactlens of claim 1, wherein the recess collects the tear fluid viacapillary action.
 10. The contact lens of claim 1, wherein the at leastone sensor is an electrochemical sensor.
 11. The contact lens of claim1, comprising a transmitter configured to transmit data relating to asensed analyte in the tear fluid.
 12. The contact lens of claim 1,comprising a processor configured to determine a concentration of asensed analyte in the tear fluid.
 13. A method comprising: collectingand storing tear fluid in a cavity disposed within a body of a contactlens when the contact lens is worn on an eye, the cavity having a closedend; storing the collected tear fluid in the cavity when the contactlens is removed from the eye; and detecting presence of at least oneanalyte in the collected tear fluid via at least one sensor locatedwithin the body of the contact lens.
 14. The method of claim 13,comprising transmitting data relating to a detected analyte in the tearfluid.
 15. The method of claim 13, comprising determining aconcentration of a sensed analyte in the tear fluid.
 16. The method ofclaim 13, further comprising dispensing a portion of the tear fluid fromthe cavity via an opening so that the portion of the tear fluid contactsthe at least one sensor.
 17. The method of claim 13, wherein thecollecting the tear fluid comprises collecting the tear fluid in thecavity via capillary action.
 18. The method of claim 15, furthercomprising transmitting data related to the presence or concentration ofthe sensed analyte to a remote device.
 19. A contact lens, comprising: atear fluid collection recess formed in a substrate that forms at leastpart of a body of the contact lens and configured to collect tear fluidwhen the contact lens is worn, the recess having a closed end; at leastone sensor configured to sense presence of one or more analytes in thetear fluid; a processor configured to determine a concentration of theone or more analytes; and a transmitter configured to transmitinformation relating to the presence or the concentration of the one ormore analytes to an external device.
 20. The contact lens of claim 19,further comprising a memory that stores information relating to the typeor the concentration of the one or more analytes.